I have just read an interesting article in this month's edition of Hifi Choice about bass management which seems to be contrary to accepted wisdom on setting "large" or "small" on AV amps. The author suggests that bass management is a far from tranparent process as apart from the phase shift that accompanies digital filterering, the redirection often causes big changes in both the levels and distortion of the signal. Comparative tests were carried out on several mid price AV amps with the speakers set to small and large comparing the amount of distortion measured on the bass signal which showed very little added distortion if there was no additional LFE signal being fed to the subwoofer but considerably more (dependant on amp) if there was LFE in addition to the redirected bass signal. Two of the amps tested showed an increase in distortion of up to 12% with speakers switched to small and LFE signal present over the comparative distortion with the speakers switched to large. A further two of the amps tested showed that the subwoofer feed increasing by 8dB just by switching from small to large which would either make a mockery of A/B testing or clip the subwoofer. According the the author the moral of the story is to set speakers to large regardless of the size of the speakers and avoid any bass management thus avoiding any additional phase shifts, changes in level or unwanted increases in distortion. I am no techie and have just paraphrased the article as an interesting discussion point for the technical gurus to get their teeth into.